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Damp Proofing

Damp in centre of party wall

Anonymous user 16/03/2024 - 2.43 PM

I have noticed a small but spreading patch of damp on an internal party wall, next to (but not on) my chimney breast. There does not appear to be damp on our neighbours side. It is relatively near to our downstairs toilet, but the toilet is very new and all the plumbing goes in the other direction to my knowledge. It is a good metre off the ground and our damp proof course is also new. Could this be due to damp coming through the chimney breast, or wouldn’t we see the damp on the breast first? It is very slight when read with a damp metre. This is a Victorian house.

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4 Answers

alliance preservation

Rating: 5 out of 5
Newcastle Upon Tyne
This could be a salt band or some salt contamination in the plaster, if you have just had a remedial DPC course Installed, they might not have took the plaster high enough in that area, if you google salt banding you should be able to compare to your problem, hope this was helpful
Answered2 August 2021
1

AnchorTie

Rating: 5 out of 5
Skelmersdale
Drill into it. Is it dry... If so yet discolored then I agree with salts above the plaster that's been replaced. With regard to a new DPC installed I would also seek a refund. Complete waste of money. The high electrical conductance meter readings originally would have been low level condensation and salts both naturally occouring and the chimney
Answered3 August 2021
0

Damp Investigations

Rating: 5 out of 5
Southall
This condition is called ammonia sulphate contamination, it’s caused by hygroscopic salts in the chimney flue . Waterproof render to that exact patch + 100mm will stop it .
Answered6 August 2021
0

Coles Basement Systems Ltd

Rating: 5 out of 5
Waltham Cross
I would definitely try looking into condensation and also has the chimney got an open pot, due to the severe weather we've had over the last couple of years it's not uncommon for the flu if not properly ventilated to penetrate moisture through the sides. Maybe the chimney was waterproof rendered so it cannot breathe so the porous plaster either side is drawing the moisture
Answered8 August 2021
0